November 29, 2020: Proper solar imaging, at last

[michael.h.f.wilkinson]

Finally got a chance to trot out the full solar kit for a longer session, across the road from where I live, so battling dying laptop batteries and the like. I set up the Vixen Great Polaris mount, and attached the APM 80mm F/6 triplet, with a Beloptik Tri-Band ERF in front.

First, I grabbed some WL data with my Lunt wedge and Baader Solar Continuum filter, using the ASI178MM. A stack of 500 out of 2000 frames gave me this:

Using a 2.5x PowerMate I got this detail shot, not brilliant as seeing wasn't great

I then swithced to the Lunt B1800S Ca-K module, and got a decent disk

Grey scale:

Pseudo colour:

Part inverted:

Part inverted + pseudo colour:

Some big prom activity to be spotted in the part inverted shots. Had I known when I shot the H-alpha, I would have prioritised those areas.

As it was, the H-alpha part had to be cut short, due to the aforementioned battery problem. I did get a couple of good shots with teh Solar Spectrum 0.3 Å H-alpha filter used with a Baader TZ-4 4x tele-centric lens and ASI714MM (which can only capture small portions of the sun. I got a mosaic of the area around the big AR:

To my surprise, the current version of MS-ICE does seem to work on H-alpha data. It really struggled in the past. I found a few other useful bits in the data intended for a full disk mosaic, which alas must be left unfinished:

 

I really need to get a 12V power supply for my laptop to prevent this from happening again. Still, it felt good to image the sun in H-alpha for the first time in ages

[Kitsunegari]

i am envious of your 2.5x powermate.

 

Mine is useless and applies a Large circle dead center in all my images,  in fact  70% of televue powermate 2.5x owners have this problem when imaging and are quite upset about it...  (not just the sun, its there on the moon too)

 

Also; my explore scientific 3x tele-extender.  has the same problem.      Whoever is building  these things are missing an important aspect of the design,  i am starting to wonder if the products are actually counterfeit?

 

 

Are you using an extension tube at all on the back of your powermate?  

[michael.h.f.wilkinson]

1 hour ago, Kitsunegari said:

i am envious of your 2.5x powermate.

 

Mine is useless and applies a Large circle dead center in all my images,  in fact  70% of televue powermate 2.5x owners have this problem when imaging and are quite upset about it...  (not just the sun, its there on the moon too)

 

Also; my explore scientific 3x tele-extender.  has the same problem.      Whoever is building  these things are missing an important aspect of the design,  i am starting to wonder if the products are actually counterfeit?

 

 

Are you using an extension tube at all on the back of your powermate?  

Sounds like some internal reflection of flat optical surfaces in the optical train. I do remember having some internal reflection issues in my Coronado scope, but not in my earlier Lunt LS35THa 

[Nigella Bryant]

Lovely captures, I managed to image the sun today to. Wonderful plages, spots, prom's and filaments. Well done.

[Kitsunegari]

2 hours ago, michael.h.f.wilkinson said:

Sounds like some internal reflection of flat optical surfaces in the optical train. I do remember having some internal reflection issues in my Coronado scope, but not in my earlier Lunt LS35THa 

IT is a reflection off the televue optics and explore scientific optics because it happens on the moon with zero filters added.  It goes away when you remove the second lens in the powermate, indicating that its the second lens....

[michael.h.f.wilkinson]

2 minutes ago, Kitsunegari said:

IT is a reflection off the televue optics and explore scientific optics because it happens on the moon with zero filters added.  It goes away when you remove the second lens in the powermate, indicating that its the second lens....

Never had an issue on the moon with either the Meade TeleXtenders (2x and 3x) or the 2.5x PowerMate in any of my scopes (Celestron C8, Meade SN6 Schmidt-Newton, and APM 80 mm F/6 triplet). As I understand it, removing the second lens group turns your tele-centric lens into a Barlow, which rather defeats the point of having them. 

[Kitsunegari]

1 minute ago, michael.h.f.wilkinson said:

Never had an issue on the moon with either the Meade TeleXtenders (2x and 3x) or the 2.5x PowerMate in any of my scopes (Celestron C8, Meade SN6 Schmidt-Newton, and APM 80 mm F/6 triplet). As I understand it, removing the second lens group turns your tele-centric lens into a Barlow, which rather defeats the point of having them. 

Only the 2x powermate is a telecentric.      You are very lucky to not have problems,     Most of us that own these do.     Help with 2.5x Powermate - SolarChat! (solarchatforum.com)

 

 

 

 

[michael.h.f.wilkinson]

37 minutes ago, Kitsunegari said:

Only the 2x powermate is a telecentric.      You are very lucky to not have problems,     Most of us that own these do.     Help with 2.5x Powermate - SolarChat! (solarchatforum.com)

 

 

 

 

Your graph shows only the 5x isn't a tele-centric, the others are good approximations. 

[paulastro]

A superb set of images Michael, I'm delighted you managed to catch it at its' best in the middle of the disk.  Alas no chinks in the cloud here yesterday, but very pleased to see your images of what I missed 🙂.

[Luke]

Very nice, my favourite is the first h-alpha.

I personally didn't find much difference between Tele Vue's PowerMate and their Barlows for solar and lunar imaging, but I may have missed a trick. Some folks seem to swear by the PowerMates.